Fuel pump



Oct. 12, 1937. L. F. BURGER 2,095,915

FUEL PUMP Filed m 5, 1935 4 Sheets-Sheet 1 Oct. 12, 1937. L. F, BURGER2,095,915

FUEL PUMP Filed July 5, 1935 4 Sheets-Sheet 2 1937. F. BURG ER 2,095,915

FUEL PUMP Filed July 5, 1935' 4 Sheets-Sheet a r7 61 L r L. F. BURGEROct. 12, 1937.

FUEL PUMP Filed July 5, 1935 4 Sheets-Sheet 4 Patented Oct. 12, 1937UNITED STATES PATENT OFFICE FUEL PUMP Leopold F. Burger, Riverside,Ill., assignor to International Harvester Company, a corporation of NewJersey Application July 5, 1935, Serial No. 30,001

1 Claim.

- complished by a centrifugal device operated by the engine. Due to thedesirability of placing such a device, usually termed a governor, asclose to the means which it regulates as possible, unit constructionshave been used, in which the governor is mounted in the pump casingdirectly on the pump shaft. It is to a construction of this type thatthe present inventionrelates.

In the operation ofcompression ignition enone method of overcoming thisdifficulty, such engines have been provided with means for lowering thecompression and starting with volatile fuel and spark ignition, such asshown in United States Patent No. 1,225,295. Means have also beendeveloped for automatically shifting from the Otto cycle to the Dieselcycle after a predetermined numberv of revolutions, as disclosed andclaimed in the pending application of Edward A. Johnston Serial No.557,997, filed August 19, 1931. In the control unit of the presentinvention, mechanism has been incorporated in the pump casing foroperating acontrol member for shifting the cycle of operation. of theengine or for other purposes for which it may be found useful in theoperation of an engine.

The principal object of the present invention is to provide an improvedcontrol'unit for solid injection engines. A more specific object is theprovision of a balanced fuel supply governor for solid injection pumps.Another object is the incorporation in a unitary structure of a pump, acontrol unit therefor, and a control unit for regulating or determininganother function of engine operation. These objects and others, whichwill be apparent from the following detailed description to follow, areaccomplished by a device as. shown in the drawings, in which:

Figure 1 is a vertical section takenjlongitudinally of a pump andcontrol unit incorporating the invention, with certain portions broker'=-way in section better .to show certain elements, as for example thepump control shaft shown by a second vertical section parallel to the.first main section;

Figure 2 is a transverse vertical section of the unit shown in Figure 1;

Figure 3 is an elevational view showing a trip 'gines, startingconstitutes a problem whenever, as, in the case of a tractor, manualeffort must be relied upon to turn the engine for starting. As-

unit particularly adapted for actuation by the control member shown inFigure 2;

Figure 4 is a. section taken on the line 2-4 of Figure 2 Figure 51s a.plan view of the rocker arms. for operating the pump ,plungers, thebearings being shown in section;

Figure 6 is a plan view of the rocker arms for operating the by-passvalves, the bearings being shown in section, and a portion of thecontrol shaft mechanism;

Figure 7 is an end elevation of the unit shown in Figure l-with thecover removed; and,

Figure 8 is a vertical transverse section taken on the'line a-a,ofFigure 1.

As illustrated, the pump and control unit are housed in a casingl'llldivided by a vertical partition ll into two compartments. An extensionhousing I2, secured to an open end of the casing, provides additionalspace for the governor mechanism. A cover plate l3 closes the open'endof the housing l2. Above the casing ID, a cylinder block I4 is secured,in which the pump cylinders are mounted. A head I5 is mounted over theblock I l and includes, formed integrally therewith, a pump casing I6,

A pump shaft l'l provided with means for conheating with an engine drivemechanism extends longitudinally of the casing I0, being provided withsuitable bearings, one of which is illustrated by the ball bearingassembly l8 mounted in the partition H. A plurality of spaced cams l0 onthe shaft I! operate rocker arms 20 pivotally mounted on a. shaft 2|.Said rocker ar'ms engage tappets 22, slidably and non-rotatably mountedin a portion of the casing l0. Said tappets operate the pump plungers23.

Rocker arms 24 pivotally mounted on eccentrics formed on a shaft 25 areprovided with extensions seated in slots 26 formed in the tappets 1 22.The rocker arms 24 are provided on their upper faces with recesses, inwhich tappets 21 are seated. Said tappets 21 operate by-pass valves, thestems 28 of which are shown in alignment with the tappets 21.

The pump as illustrated and described up to this point is ofa'conventional construction now in wide commercial use. Adjustment ofthe shaft 25 alters. the time of by-pass, thereby controlling theeffective stroke of the pump plungers and the charges of fuel deliveredthereby.

The shaft I1 is provided with a carrier 29 on which governor weights 30are pivoted on diametrically located, parallel axes. Said weights aresubstantially arcuate in shape, fitting around mitted to a sleeve 35concentric with respect to the sleeve 34 and piloted on said sleeve. Thesleeve 35 is slidably fitted into a cup-like member 36, which is in turnslidably fitted in a bore formed in the housing l2. A compression spring*31 abutting the inside 'of themember 34 abuts a pilot member 38,through which pressure is transmitted in an axial direction on a flangeformed on the sleeve 35. It will be understood that by this constructionthe spring 31 opposes the force developed by centrifugal action on theweights 30.

As a stationary limiting adjustment for the member 36, nuts 36 arethreaded on a stud secured to a portion of the housing I2. One of saidnuts overlaps the head portion of the member 36, (as shown in Figure 7),thereby limiting outward movement of said member.

A bell crank member 39 is pivotally mounted on a pivot pin 40 extendingtransversely of the axis of the shaft l1 above said shaft. Said memberis provided withspaced, downwardly extending, lever arms 4|, which carrymembers 42 positioned between spaced flanges 43 on the sleeve 35. Bymeans of this construction, reciprocating movement of the sleeve 35-oscillates the bell crank member 39.

The member 39 also carries an upwardly extending lever arm 44, whichcarries means for engagingspaced flanges 45 mounted on a shaft 46. Saidshaft is mounted for reciprocation on an axis parallel to the axis ofthe pump shaft l1. At its inner end, the shaft 46 is provided with athreaded adjusting member 41, by which the effective compression of a,spring 48 may be regulated. Said spring abuts a stop carried by aportion of the casing in. At its other end the shaft 46 abuts one endofa rocker member 49 rigidly secured to a transverse shaft 56 pivotallywith the rocker arm 49, carries an adjusting le- I ver 5| at one end,through which a threaded adjusting member 52 extends. By the adjustmentof said member the maximum angular position of the rocker member, actingto increase compression on the spring 31, is limited. Outside thecasing, the shaft 56 carries a lever 53 for manual operation to effectspeed change of the engine by control of the fuel supplied thereto.

The bell crank member -39 carries integral therewith an extension 54formed as a. sector of a gem, by which rotary motion is transmitted to agear 55 non-rotatably mounted on the pump control shaft 25.

Intermediate its end the shaft I1 is provided with a worm wheel 56positioned to engage and drive a worm gear 51 mounted on a verticalshaft 58. Said shaft. is carried by the casing I 0 and extends upwardly,as shown in Figure 2, above 'the broken away portion to drive the pumpin the casing I 6. This part of the mechanism has not been shown, as itis not involved in the present invention. The shaft 58 carries a wormgear 59, which drives a worm wheel 60 on a transverse shaft 6| carriedby the casing I 0. Said shaft is provided with an eccentric 62, on whicha ratchet member/63 is pivotally mounted. Said ratchet member is springpressed by a member 64 mounted in a bore formed in a portion of thecasing I0 into engagement with a toothed ratchet member 65. A springpressed latch 65' holds the ratchet member 65 against rotation in anangular direction opposite to the direction in which it is rotated bythe ratchet member 63. The member 65 is rigidly carried by a shaft 66,rotatably mounted in the casing Ill and extending outside the casing formanual operation to set the ratchet member 65.

A cam 61 on the shaft 66 is positioned to engage a plunger 68. Saidplunger operates a push rod 69, the lower end of which is shown inFigure 4 and the uper end of which is shown best in Figure 2.

Said shaft may control any desired function of engine operation,preferably a control for shifting from Otto'cycle to Diesel cycle, asdisclosed and claimed in the Johnston application previously referredto.

The operation of the trip mechanism will be clear from the descriptionof the parts. The ratchet member 63, continuously driven at a reducedspeed from the shaft l1, engages the notches of the ratchet member 65,slowly rotating said member. By means of the hand adjustment provided bythe shaft 66 extending outside the casing, the ratchet member 65 may beset with the cam 61 in any desired position. For example, said cam maybe set at such an angular position with respect to the plunger 68 that600 revolutions of the engine will be required to lift the push rod 69into tripping position with respect to the member 12. The cam may be setat any location from its maximum to a position where the latch will betripped by a very few engine revolutions. This mechanism is particularlyuseful in connection with shifting from Otto to Diesel cycle, aspreviously pointed out. It is a unique construction in that it iscombined with a fuel pump in a unit construction.

The operation of the governor for shifting the control shaft 25 andvarying the effective length of the pump stroke thereby is conventionalin commercial pumps. Applicant, however, has provided an improvedbalancing means and limiting stops to improve the functioning of thepump, particularly to reduce what is known in governor action ashunting? or surging. The regulating spring 48, which opposes action ofthe spring 31, has the function of a secondary control, which can beaccurately adjusted to obtain a more uniform governor action. To providemeans for varying the range within which the governor operating meansmay be connected to the lever 53. Referring to Figure 1, manualoperation of the shaft 50 in a counter-clockwise direction moves therocker member 49, which is carried by the shaft, in the same angulardirection. 'The lower end of the member 49 abuts the head por tion ofthe cup member 36. Movement of this v member to the right compresses thespring 31 abuts the stop formed by the nuts 36'. determines the minimumspeed at which full and in effect increases the speed of the engine, asa higher speed is required for the governor weights to compress thespring and to move the bell crank member 39 for effecting a reduction infuel supply. To. limit the increase in speed which can be given to theengine by the manual adjustment, an adjusting stop 52 is provided on alever 5| carried by the shaft 50. When the stop 52 abuts the end wall ofthe housing, as shown in Figure 7, the spring cannot be furthercompressed and the speed of the engine cannot be increased- It is to beunderstood that, at any manual setting, thegovernor is effective tomaintain the speed for that setting as predetermined by the governorconstruction and the compression rate of the spring 31 and the auxiliaryspring 48.

1, to reduce the speed of the engine, the cup meniber 36 moves outwardlyto the left until it This stop governor action is available. For furtherdecreases in speed the member 49 is manually-rotated in a clockwisedirection to move the shaft 06 to the right, thereby rocking the bellcrank member 39 and rotating the control shaft 25 to reduce the amountof fuel injection. By this manual means the injection of fuel may bereduced to a minimum, or to zero, for stopping the engine, if theby-pass valves are constructed for a zero amount of injection.

By the means above set forth, a governor is provided which is effectiveto maintain a given speed at any of a wide range of settings. The

manual control for changing the effective range also incorporates meansfor manually reducing the fuel supply for idling or for stopping theengine.

It is to be understood that applicant has shown and described onlycertain preferred constructions illustrating the principles of hisimproved pump and control unit and that lie-claims of the pump,centrifugal governor weights mounted on the pump shaft, a governorreciprocated member positioned in alignment withthe pump shaft andadapted to be operated by the governor weights, a spring positioned toabut a portion of said member for counteracting the force of thegovernor weights, fixed abutment means for adjusting the pressure onsaid spring, a double' bell crank mounted on an axis transverse to theaxis of the pump shaft, a lever arm on said crank connected to thegovernor reciprocated member, a lever connected to the bell crank andoperatively connected to. the pump control member, a second lever armcarried by the bell crank, a control member'operatively connected tosaid crank for reciprocation thereby, a rocker, arm mounted on a shafttransverse to the axis of the pump shaft having an arm engaged by oneend of said control member, an adjustable stop carried by said rockerarm, and manually operable means for operating saidrocker arm.

LEOPOLD F. BURGER.

